8/13/2019 2008 Exam Choice Physics Solutions
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Exam Choice
2008 Physics Trial HSC examination. Marking Guidelines and model
Answers.
Section I A Multiple Choice
1 2 3 4 ! " 8 # 10 11 12 13 14 1
$ % C % % $ A % C % % C A C A
Part $1!
Mar&in' Criteria Mar&s
Appropriate technology identified and sound explanation provided
2
An appropriate technology identified 1
e.g. Photogates were used to measure the time taken for a
projectile to fall as these are much more accurate than hand-held
stopwatches.
1" a(
Mar&in' Criteria Mar&s
Full and correct explanation linking movement of oject with
force needed and therefore work done 2
Movement of oject referred to !" force causing motion identified
1
#o increase an oject$s gravitational potential energy% a force
must act on the oject to move it against the gravitational field it
is within. Aforce moved through a distance e&uates to work
done% therefore work has een done in increasing an oject$s 'P.
1" )(
Mar&in' Criteria Mar&s
(orrect method used to calculate correct answer 2
An incorrect )GP'*mgh+ method used !" error made in correct
calculation 1
,ork done * change in 'P
at //km P at surface
at //km at surface
at //km at surface
00 12 1
3
' ' '
0 0
0 04.45 0/ 4./ 0/ 6./ 0/
445/ 0/ 45/ 0/
0.2 0/ 7
P P
earth object earth object
earth object
m m m mG G
r r
Gm mr r
=
=
=
=
= )8ote 0.6 x 0/37 is answer y simply doing GP'*mgh+
1" c(
Mar&in' Criteria Mar&s
(orrect reasons given% i.e. satellite must have orital velocity
re&uiring more work to e done 2
A reason identified 9 e.g. satellite is in motion 1
,hen a satellite is launched% work is done to increase its
gravitational potential energy A8: its speed so that at its
allotted altitude% it hassufficient speed to continue to orit the
'arth. #hus much more work is done than simply lifting it straight
up.
18 a(
Mar&in' Criteria Mar&s
(orrect data sustituted into correct e&uation to arrive at
correct answer 2
(orrect data identified !" appropriate e&uation attempted
with error)s+ 1
1
;
3.< m s
/ )at max. height+
6/./ m
y
y
y
u
a
v
y
=
=
=
=
1 1
1
1
0
1
/ 1 3.< 6/
3
